Vibrate or Tumble

[Stepside]

I am looking for ideas on what to use to put a uniform finish on metal parts. Metals to include steel, aluminum and brass. It would be nice if it could do light deburring at the same time. parts would be smaller than 2 inch by 6 inch by 1/2 inch. Whatever choice is made I would like to build the device.

[wierdscience]

Abrasive blasting is the most versitle,options include silica sand,aluminum oxide,glass beads,black slag,walnut hulls,soda,crsuhed glass,corn cob,steel shot and coffee media.

You will need a decent compressor(120 psi at least 12cfm free air)though.

I have a HF vibratory drum,it's okay,but slow and won't take liquid.

HF does however sell extra drums for the machine at around $12 including walnut shells.

I have been thinking recently of making one with three drums on one base using my own motor and belt driven.Then fluid could be used and increse the effect.

[dalee100]

Hi,

Abrasive blasting is a nicer finish. But tumbling, (drum type, not vibratory), will do more parts faster and cheaper. So it depends on how nice a finish you need, how many parts you are doing, and how much you want to spend to do them.

dalee

[Just Bob Again]

I have a vibrator and a tumbler. Vibrator works faster. Does useful work in a couple hours. Would have to be fairly large to take a 6-inch piece. Mine won't. The design of the bowl is important for it to properly tumble and feed the media. I don't think I'd try to build a vibrator. You also need the right media and it isn't really cheap. A tumbler is easy to make but slow. A day or two run time, depending on the media. I've made tumblers that will take 3 5-gallon plastic pails for larger stuff or quantities. You can use sandblasting sand or corncob with rouge or play sand or whatever you have handy. The vibrators really want commercial media.

Blasting is instant gratification. Possible to do some damage to the part if you're not careful, but quick. For polished parts, I use the tumbler. For coloring and light deburring, the vibrator. I have a miniature sandblaster, too. Made for graphic arts use. A Badger. Only needs like 1 CFM of air and it's cheap. I think it was $20. Good for very small parts but would be very slow on something 6 inches long.

[Peter Neill]

My limited experience with abrasive (bead) blasting, is that very often the finish can be anything but uniform.
It's quite easy to get patches of different texture, depending on how long you blast for or how close you blast from, IMHO.

Peter

[Circlip]

And how CLEAN the abrasive is, and you dont blast Stainless or Alloy with some thats blasted Steel.

[Rustybolt]

A serviceable tumbler can be made from a portable cement mixer. I have used them , both types, to mainly knock off burrs. Depending on the media you can get a bright polish to a dull matte finish. My personal opinion is that the vibratory type is more versitile, while the tumbler type is easier to build.
If you do decide to build your own, Devcon makes a pourable rubber to line it with. Otherwise the noise will drive you nuts.